Water is essential for life and covers much of the Earth's surface, though most is saline and found in oceans, while freshwater exists as ice, in lakes, rivers and underground. All living things need water to survive as it is crucial for cellular and biological processes. The amount of water in an area along with other factors like temperature and soil composition determines what types of species can live there and their population sizes. Water pollution occurs when harmful substances from sources like sewage, agriculture, factories and oil spills contaminate water supplies, negatively impacting both the environment and human health.

1. Water A wonder liquid

2. A very large area of
the earth’s surface is
covered with water.
Water is also found
inside the earth, in
the atmosphere as
water vapour.
The water in seas
and oceans is saline.
Fresh water is found
in rivers, lakes,
ponds and as ice and
snow at the poles
and mountains in
cold regions.

3. Water is needed by
living organisms
because all life
processes and cellular
activities need water.
So all organisms need
water to survive.
The amount of water
and other factors like
temperature and
nature of soil
decides the diversity
of species and the
number of
individuals of each
species in an area

4. Water pollution

5. Sewage
(Wastewater)
Underground storage
leakages and oil pollution
Atmospheric
deposition
and Global
warming
Industrial
waste

6. The increase in the
content of harmful
substances in water
is called water
pollution. Water pollution is caused by
addition of harmful
substances like fertilisers
and pesticides from farms,
sewage from towns, cities
and factories, harmful
chemicals from factories

9. Industrial waste…
• Many industries use freshwater as a
source to carry away harmful
chemicals and waste away from the
plant and dump them into rivers, lakes
and oceans.
.

11. Underground storage
leakages and oil pollution…
• Underground storage tanks often
store substances like petroleum. If UST’s
made from steel pipes are directly exposed
to the environment, the steel can corrode
and cause leakages, affecting surrounding
soil and groundwater.